A 15-year-old boy suspected of shooting and critically wounding a fellow student on the first day of classes at a Baltimore high school has been charged with first-degree attempted murder, police said Tuesday.

Robert Wayne Gladden Jr. is being charged as an adult and also faces a first-degree assault charge stemming from Monday's shooting, according to Baltimore County Police Department spokeswoman Susan Hunt.

Hunt said Gladden, who is being held without bail, is cooperating with authorities. A preliminary hearing has been scheduled for Sept. 7.

The shooting took place just before 11 a.m. at Perry Hall High School, voted one of America's Best High Schools by Newsweek magazine in 2010, in suburban northeast Baltimore.

Police believe the attacker chose his victim at random, another police spokeswoman, Julia Hardgrove, said on Monday. She said several other students suffered minor injuries.

The suspect was tackled by faculty members and held until police arrived, officials said.

The shooting is the latest incident of gun violence in a summer plagued by troubling shootings in the United States.

In July, a gunman killed 12 people and wounded 58 at a movie theater in Aurora, Colorado. In August, a suspect described by authorities as a white supremacist killed six people outside a Sikh temple in Wisconsin before committing suicide.